Tension in music refers to moments of harmonic instability or dissonance that create an unresolved feeling. It adds excitement and interest to the music before resolving into more stable and consonant sounds.
Related terms
Resolution: Resolution is when musical tension is resolved by moving from dissonant chords or notes to more stable and consonant ones.
Dissonance: Dissonance refers to harsh or clashing sounds that create tension in music.
Suspension: A suspension occurs when a note from one chord is held over into the next chord, creating temporary dissonance before resolving.